text: from simpleflow import Workflow, futures
  from simpleflow.canvas import Chain
  
  
  class MarkerWorkflow(Workflow):
      name = 'example'
      version = 'example'
      task_list = 'example'
  
      def run(self):
          m = self.submit(self.record_marker('marker 1'))
          m = self.submit(self.record_marker('marker 1', 'some details'))
          self.submit(self.record_marker('marker 2', "2nd marker's details"))
          futures.wait(m)
          markers = self.list_markers()
          assert 2 == len(markers)
          print('Markers: {}'.format(markers))
          markers = self.list_markers(all=True)
          assert 3 == len(markers)
          print('Markers, all: {}'.format(markers))
  
  
  class MarkerInChainWorkflow(Workflow):
      name = 'example'
      version = 'example'
      task_list = 'example'
  
      def run(self):
          chain = Chain(
              self.record_marker('marker 1'),
              self.record_marker('marker 1', 'some details'),
              self.record_marker('marker 2', "2nd marker's details"),
          )
          futures.wait(self.submit(chain))
          markers = self.list_markers()
          assert 2 == len(markers)
          print('Markers: {}'.format(markers))
          markers = self.list_markers(all=True)
          assert 3 == len(markers)
          print('Markers, all: {}'.format(markers))
  